Solar Eruption

NASA

The STEREO (Ahead) spacecraft observed this visually stunning prominence eruption on Sept. 29, 2008, in the 304 angstrom wavelength of extreme UV light. Prominences are relatively cool clouds of gas suspended above the sun and controlled by magnetic forces.

The prominence rose and cascaded to the right over several hours, appearing something like a flag unfurling, as it broke apart and headed into space. The prominence is composed of ionized Helium that is about 60,000 degrees Kelvin.